Method of producing thymol



Patented June 30, 1931 UNITED srArs rENT Q WALTER SGHOELLER, 0Fnnnrirn-onennorrnnnnne,"HANS mmnaosjs r STEGLITZ, AND REINI-IARD GLER-C,or BERLI1\T, GERMANY, ASSIGNQRS To THE FIRM scHERINe-KAHLBAUM A. e, orBERLIN, GERMANY V METHOD or momma rnYMOL'P i No Drawing. Applicationfiled November 22,1928, Serial No. 321,266, and in- .GernianyNovember24,1927.

Our invention refers to the production of thymoland has for oneof itsobjects a meth- 0d whereby thymol can be produced from hydroxythymol, acompound first described by Fries and Fickewirth in Annalen der Chemie,vol. 362, page 40, as having the constitution and, on being heated,being converted, by the splitting off of water, into3-methyl-6-isopropylenphenol.

We have now found that if the heating operation accompanied by thesplitting off of water is carried through inthe presence of vantage onsuch a surface catalyst.

The process accordingto the present invention can also be carriedthrough in the presence of a solvent and/or under elevated pressure, asusual in hydrogenation processes.

- Example 1 Hydroxythymol is treated in an autoclave at about 1201'Z0C.-with hydrogen in the presence of 35 per cent'by weight of a nickelcatalyst of the kind adapted for use in hydrogenation, until 2 atomshydrogen have entered the molecule, whereby thymol is obtained.

Ewample 2 p Hydroxythymol is dissolved in an equal quantity of methaneand the solution is treated as described with reference to Example 1,

whereby the hydroxythymol is quantitatively L converted into thymolwhich is freed from the solvent by distillation.

' Example 3 Hydroxythymol is exposed in the presence of 3 5 per cent byweight of a hydrogenation disclosed in the foregoing specificationwithout departlng from thelnventlon or sacr1 ficing the-advantagesthereof.

In the claims aflixed to this specification no selection of anyparticular modification of the lnvention 1s lntended to the excluslon ofother modifications thereof and the right to subsequently make 'claim toany modification not covered by these claims is expressly reserved.

We claim q 1. The method of producing thymol comprising acting withhydrogen at 120-170 C. in the presence of a hydrogenation catalyst onhydroxythymol, until 2 atoms hydrogen have been combined. 7

2. The method of producing thymol comcatalyst and 5-10 per cent of asurface catav lyst, for instance franconite, in an autoclaveprisingacting with hydrogen at 120170 C.

in the presence of a solvent and a hydrogenation catalyst onhydroxythymol, until 2 atoms hydrogen have been combined.

3. The method of producing thymol comprising acting with hydrogen at120-170-C.

and under a pressure above normal in the presence of a hydrogenationcatalyst on hydroxythymol, until 2 atoms hydrogen have been combined.

4:. The method of producing thymol comprising acting with hydrogen at120-17 0 C.

in the presence of a hydrogenation catalyst and a substance ofgreatporosity and correspondingly large surface on hydroxythymol, until 2atoms hydrogen have been combined.

5. The method of producing thymol comprising acting with hydrogen at120-170 C. in the presence of a hydrogenation catalyst, deposited on asubstance of great porosity and correspondingly large surface, onhydroxythymol, until 2 atoms hydrogen have been combined.

In testimony whereof We afiiX our signatures.

WVALTER SCHOELLER. HANS JORDAN. REINHARD CLERC.

